I appreciate your answer but in fact I want to define the solver inside the code since I have different solvers for different systems. So I rewrite the question: How to call a direct solver with something like 'linear_solver->set_solver_type'? Thanks Paulo
> On Thu 2008-04-10 14:09, [EMAIL PROTECTED] wrote: >> Hi, >> How can I use a direct solver to solve a linear system of equations? >> Thanks in advance, >> Paulo > > You can do this entirely with PETSc command line arguments. For instance > > -ksp_type preonly -pc_type lu > > will solve the system using LU decomposition. If your matrix is > symmetric, you > can try -pc_type cholesky. You can select different direct solvers by > changing > the matrix type with -mat_type. Run the program with -help and you will > see the > supported types (such as umfpack, superlu, aijspooles, sbaijmumps). > Depending > on the problem, you may want to try preconditioning with algebraic > multigrid. > You can build PETSc with libraries like Hypre, ML, and Prometheus, then > use > -pc_type hypre. For 3D problems, I find this starts beating a direct > method > for quite small sizes. > > Jed > > ------------------------------------------------------------------------- > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > Don't miss this year's exciting event. There's still time to save $100. > Use priority code J8TL2D2. > http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone > _______________________________________________ > Libmesh-users mailing list > Libmesh-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/libmesh-users > ------------------------------------------------------------------------- This SF.net email is sponsored by the 2008 JavaOne(SM) Conference Don't miss this year's exciting event. There's still time to save $100. Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone _______________________________________________ Libmesh-users mailing list Libmesh-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/libmesh-users
